MAX FAX Flashcards
What foramen does the ophthalmic branch of the trigeminal nerve pass through?
superior orbital fissure
What foramen does the maxillary branch of the trigeminal nerve pass through?
Foramen rotundum
What foramen does the mandibular branch of the trigeminal nerve pass through?
Foramen ovale
What is the origin, insertion, innervation and function of the muscles of mastication:
Masseter:
o Origin – zygomatic arch
o Insertion – lateral surface and angle of mandible
o Action – elevates and deep fibres retrude mandible
o Testing – clench teeth together
o Innervation – masseteric branch of mandibular division of trigeminal nerve
- Temporalis:
o Origin – floor of temporal fossa
o Insertion – coronoid process and anterior border of Ramus
o Action – elevates and retracts mandible
o Testing – clench teeth and palpate all fibres (anterior, middle and posterior)
o Innervation – anterior division of deep temporal nerve branches of mandibular division of trigeminal nerve - Medial pterygoid:
o Origin – superficial head (maxillary tuberosity) Deep head (Medial side of lateral pterygoid plate)
o Insertion – medial surface of angle of mandible
o Action – elevates and assists in protrusion of mandible
o Testing – intra oral can be painful
o Innervation – nerve to medial pterygoid of the mandibular division of trigeminal
nerve - Lateral pterygoid:
o Origin – lateral surface of lateral pterygoid plate and base of skull
o Insertion – pterygoid fovea and some fibres extend into the capsule of the TMJ
independent heads – inferior to head of consult; superior to intra articulate disc
Action- mandibular protrusion & depression
o Testing – response to resisted movement by putting finger far back of maxilla
and move jaw side to side
o Innervation – anterior division nerve to lateral pterygoid branch of mandibular division of trigeminal nerve
What is the pathology of a squamous cell carcinoma?
2 main factors involved:
* Genetic
* Carcinogens (environmental factors)
Damage alters gene expression - altering cell function.
Initiation- carcinogen causing genetic change.
Promotion- cell multifplication
Transformation- production of malignant cell.
Progression- forming malignant tumours.
Patient comes in with a right body mandibular fracture
- Other than pain, bruising and swelling. List 6 other signs and symptoms
associated with mandibular fractures
2020 Paper 1 Q9
- Limited function (opening and lateral movements)
- occlusal derangement = Can’t bite as normal into ICP
- Numbness lower lip
- Mobility of teeth/loose teeth
- Bleeding limited to area of fracture
- AOB
- –when ramus is shortened by trauma (posterior teeth meet prematurely)
—-Subcondylar (bilateral) Causes shortening In vertical height of ramus = AOB - Facial asymmetry
- deviation of mandible towards opposite side to fracture
- Bleeding in FOM = sublingual haematoma
- Steppy deformity of the teeth.
Two radiographic views required for mandibular fractures
2020 Paper 1 Q9
2 Plain views at 90 degree angles to each other
* OPT + posteroanterior mandible
OPT- Orthopantomogram
Other radiographs:
* Occlusal
* Lateral oblique
* Towns view
* SMV
* CT scan or CBCT
What factors cause displacement of mandible fractures? (6)
2020 Paper 1 Q9
- Direction of fracture line (Muscle can encourage or prevent displacement)
- Opposing occlusion: prevents fracture being displaced
- Magnitude of force
- Mechanism of injury
- Intact soft tissue: intact tissue = displacement unlikely
- Other associated fractures: > 1 fracture = higher chance of displacement
What are 6 signs and symptoms of TMD?
- Intermittent pain of several months or years duration
- Muscle / joint / ear pain, particularly on wakening
- Trismus / locking/limited mouth opening
- ‘Clicking/popping’ joint noises
- Headaches
- intra-oral signs: linea alba and tongue scalloping
What 2 muscles should be palpated when querying TMD?
masseter
temporalis
What are the common causes of TMD? (8)
- Myofascial pain (common. Problem with muscles due to overworking)
- Disc displacement (common)
– Anterior with reduction: where the disc slips forward but can move back to its original place
– Anterior without reduction - Degenerative disease (less common)
– Localised e.g. osteoarthritis
– Generalized (Systemic) e.g. rheumatoid arthritis - Chronic recurrent dislocation – condyle gets stuck in front of the eminence and mouth is locked open
- Ankylosis – condyle fused to the base of the skull (most people have a psudoankylosis)
- Hyperplasia – one condyle grows more than the other (can be bilateral but nota s common)
- Jaw moves to the opposite side from where the hyperplasia is
- Neoplasia (osteochondroma, osteoma, or sarcoma)
- Infection – can result in ankylosis
What 3 nerves supplies the TMJ?
auriculotemporal, masseteric, posterior (deep) temporal nerve
- Patients with TMJ pain can also experience discomfort in the ear as the auriculotemporal nerve also provides sensation to the external auditory meatus
What conservative advice is given to manage A patient with TMD?
Patient education!!
Counselling/reassurance: why its happening, how it happens, what the causes are, how we manage etc.
Advice: (standard approach)
* Reassurance
* Soft diet
* Masticate bilaterally
* No wide opening
* No chewing gum
* Don’t incise foods
* Cut food into small pieces
* Stop parafunctional habits e.g. nail biting, grinding
* Support mouth on opening e.g. yawning
Medication
- NSAIDs
- Muscle relaxants
- Tricyclic antidepressants (have muscle relaxant properties)
- Botox of masseter = prevents clenching (last resort tx)
- Steroids
Physical therapy
- Physiotherapy
- Massage/heat
- Acupuncture
- Relaxation
- Ultrasound therapy (not used as much)
- TENS (Transcutaneous Electronic Nerve Stimulation)
- Hypnotherapy and CBT
Splints
- Bite raising appliances
- Anterior repositioning splint e.g. wenvac or Michigan splint
What are the mechanisms of a bite splint using in TMD?
They stabilize the occlusion and improve the function of the masticatory muscles, thereby decreasing abnormal activity.
They also protect the teeth in cases of tooth grinding
- Eliminated occlusal interference
- Habit breaker
- Reduces loading on TMJ
- Prevents the join head from rotating so far posteriorly in the glenoid fossa
(same answer as above but lara order) x
Elimates occlusal interference
acts as a habit breaker
Reduces load on TMJ.
Improves function of mastiagtory muscles by decreasing the abnormal activitu and protecting the teeth in case of tooth grinding.
What is arthrocentesis?
Arthrocentesis = wash of the joint = increase lubrication
- Under LA or GA
- Inject lactate, hyaluronic acid and steroid into the capsule
- Can lead to reduction of the disc and increase function
Action: Breaks fibrous adhesion and flushes away the inflammatory exudate to increase lubrication.
Give 2 possible surgical options for TMD?
- Menisectomy = remove the disc completely
- Disc plication = move the disc to correct position
- Eminectomy = remove part of the boney eminence
What are 6 signs and symptoms of Zygomatico-orbital complex fractures involving orbit floor?
Diplopia and restricted eye movement
paralysis of eye
numbness under the eye
pain, bruising, swelling
flat face
facial asymmetry
What imaging would you take to confirm Zygomatico-orbital fracture diagnosis?
occipitomental view at 15 and 30 degrees
What are the management options for Zygomatico-orbital complex fractures? (7)
- initial and correction
Initial:
* Exclude ocular injury
* Prophylactic AB’s
* Avoid nose blowing
- Review once swelling subsided
- Further radiographs (+/- CT)
- Informed consent
Correction:
* Closed reduction +/- fixation
- howard gillies approach
* Open reduction + internal fixation
- Most corrections have ORIF
oral cancer
- What does dentally fit mean?
Patient who is free of pain & infection or future sources of pain&infection
OC - What is a multi disciplinary team?
A team of individuals from a variety of disciplines who work together to provide holistic treatment/care for a patient
List 4 members of an MDT for someone being treated for oral cancer?
Oncologist, special care dentist, Maxillofacial surgeon, speech and language therapist, physiotheraptist, radiographer
What risks is the patient at following radiotherapy, apart from mucositis? (5)
- traumatic Ulceration,
- mucositis
- Fibrosis of the muscles/soft tissues = Trismus
- xerostomia = Dry mouth from damage to the salivary glands
- Dental caries from the dry, acidic mouth
- dental erosion
- periodontal disease
- increased candida infections
- reactivation of herpes simplex virus
- Endarteritis obliterans (damge to the blood vessels supplying the bone) = osteoradionecrosis
What are the oral side effects of chemotherapy? (5)
Cytotoxic
* mucositis
* Decreased salivary gland function (Xerostomia)
Bone marrow supression causing:
* Defective haemostasis (Decreased neutrophils/ platelets/RBCs) increasing bleeding risk.
* Greater infection risk (Oral candidiasis/ Herpes simplex)
Neurological
* Trismus
* Joint pain.
Nausea/vomiting = erosion
Any teeth mineralising during chemotherapy- Disturbed root formation/ microdontia/ crown hyperplasia/ Hypodontia.
General conditions:
reduced RBC = anaemia
reduced WBC = leukopenia
reduced platelets = thrombocytopenia
reduced neutrophils = neutropenia
hairloss
fatigue/tiredness
What are the grades of mucositis?
Grade 0 = no alterations
grade 1 = pain and erythema
grade 2 = erythema and ulcers
grade 3 = ulcers (liquid diet)
grade 4 = unable to feed
How is mucositis managed? (3)
Avoid:
- Smoking
- Spirits
- Spicy food
- Tea and coffee
- Non-prescription mouthwash (esp those with alcohol)
Topical:
- Lignocaine gel
- Saline mouthwash (good for use in radiotherapy)
- Sodium bicarbonate mouthwashes (good for use in radiotherapy)
- Caphosol (manmade mucous/saliva sub)
- Tea tree oil mouthwash
- Cooling using ice cubes
low level laser light therapy
How can mandibular fractures be classified? (7)
- Involvement of the surrounding soft tissue;
* Simple: surrounding soft tissue intact
* Compound: fracture exposed to the surrounding environment (soft tissue breached)
Need AB’s
* Comminuted: multiple small fragments e.g. from gunshot - No of fractures
* Single
* Double
* Multiple - side of fracture
* Unilateral
* Bilateral - Site of fracture
* Angle
* Below condyle (subcondyle)
* Parasymphyseal (in the middle)
* Body
* Ramus
* Coronoid
* Condylar fracture (intra/extra caspular)
* Alveolar process - Direction of fracture line
* Favourable: direction of fracture line limits the displacement of the fracture by the action of the surrounding muscles
* Unfavourable: direction of fracture line encourages the displacement of the fracture - Specific fractures
* Green stick fracture: soft bone (children) very unlikely to completely fracture = still attachment in one of the cortices
* Pathological: fracture caused by pathology
e.g. osteoporosis, osteomyelitis, Padgets, expanding cystic lesion - Displacement of the fracture
* Displaced: requires surgical tx
* Undisplaced: may not require surgical intervention
How is a mandibular fracture managed?
2020 Paper 1 Q9
Control pain and infection - analgesia and antibiotic (if a compound fracture)
- Undisplaced = usually no tx
- Displaced or mobile fracture = surgical intervention
a) Closed reduction + fixation: reduce the fractured segments to their normal anatomical orientation without exposing the fracture line (we judge it using Intermaxillary fixation = if teeth go into ICP )
b) Open reduction + internal fixation
Reflect ST and expose the bone to reduce the segment
Open reduction and internal fixation (ORIF) = most common
What are the signs and symptoms of maxillary fractures? (7) *** have we done
Pain, asymmetry, diplopia, altered sensation, swelling, nose bleed, mobility.
Describe the Le Fort Classifications.
Type 1 – horizontal maxillary fracture spreading teeth from upper face (floating palate)
Type 2 – pyramidal fracture involving nasofrontal suture (floating maxilla)
Type 3 – transverse craniofacial disjunction where maxilla is detached from base
of skill (floating face)
Surgical Classifications:
Le Fort I osteotomy (most common)
- LF1 = Cut the maxilla from the base of the skull and move it in any direction
- LF2 = maxilla and nose moved together
- LF3 = Maxilla, nose and cheek bone moved together
What radiographs would you use to image a maxillary fracture?
occipitomental view 15* & 30*
how are maxillary fractures managed?
What is a cyst?
A pathological cavity having fluid, semi-fluid or gaseous contents & which is not created by the accumulation of pus.
Allows it to gradually increase in size
Give 2 inflammatory cysts (4)
(Odontogenic)
radicular cysts (&residual cysts)
Inflammatory collateral cysts
- paradental cyst
- buccal bifurctaion cyst
Give 2 developmental cysts (4)
Odontogenic:
dentigerous cysts
odontogenic keratocysts
lateral periodontal cyst
non-dontogenic
nasopalatine duct cyst
Give 2 non-odontologenic cysts (3)
nasopalatine duct cyst
solitary bone cyst
aneurysmal bone cysts
Give 2 common treatment options for cysts with advantages and disadvantages for both?
- Enucleation
What is it?
All of the cystic lesion is removed (entire cyst lining removed with the associated tooth/root if present)
Treatment of choice for most cysts
What are the Advantages?
* Whole lining can be examined pathologically
* Primary closure
* Little aftercare needed
What are the Contraindications/disadvantages?
* Risk of mandibular fracture with very large cysts
* (Dentigerous cyst) wish to preserve tooth
* Old age/ill health can’t be put under GA
* Clot-filled cavity may become infected
* Incomplete removal of lining may lead to recurrence
* Damage to adjacent structures
* Daughter cysts in the keratocyst lining – to remove all of these would cause damage to adjacent structures/anatomy = have to use marsupialisation
- Marsupialisation (less invasive and can be done under LA)
Requires cooperation
- Creation of a surgical window in the wall of the cyst, removing the contents of the cyst & suturing the cyst wall to the surrounding epithelium
- Encourages the cyst to decrease in size & may be followed by enucleation at a later date
- Always a window present with something inside for up to 6 months e.g. an obturator to prevent tissues growing back over it
What are the Advantages?
* Simple to perform
* May spare vital structures
What are the Contraindications/disadvantages?
* Opening may close & cyst may reform
* Complete lining not available for histology
* Difficult to keep clean & lots of aftercare needed
* Long time to fill in
How does a radicular cyst develop? (6)
Always associated with a non-vital tooth and always attached to a tooth
- Initiated by chronic inflammation at apex of tooth due to pulp necrosis
- Proliferating epithelium with central necrosis (bringing fluid in)
OR epithelium surrounds fluid area - Continued growth
- Osmotic effect with semi-permeable wall
- Cytokine mediated growth
How does a radicular cyst appear histologically and radiographically?
Radiographically:
* Well-defined, round/oval radiolucency
* Corticated margin continuous with lamina dura of non-vital tooth
* Larger lesions may displace adjacent structures
* Long-standing lesions may cause external root resorption &/or contain dystrophic calcification
Histologically:
- Epithelial lining (often incomplete) = non k stratified squamous epithelium
- Connective tissue capsule
- Inflammation in capsule
Dark blue dots nuclei of inflammatory cells
Cholesterol clefts
Mucous metaplsia
Hyaline/rushton bodies
(Niamh)
Orthognathic surgery
- What are the indications for orthognathic surgery? (3)
- Pt with aesthetic or functional concerns
- Growth completed
- Moderate/Severe skeletal discrepancy
- A-P
- Transverse
- Vertical
- What are the risks of orthognathic surgery? (6)
Relapse
Nerve damage
Bleeding
Unobtainable results for patients with high expectations
Infections
TMJD
What investigators are carried out before orthognathic surgery? (3)
Radiographs:
* OPT
* Cephalographs
* Periapicals
* Occlusal
* CT scanning
All patients have a CBCT nowadays.
- Study Models (casts)
- Photographic (2D, 3D)
Stereophotogrammetry = 3D imaging
Give 2 types of mandibular orthognathic surgery
- Advancement = Sagittal split mandibular osteotomy
- Ramus is split from the body to allow the anterior part of the (body and the dentition) mandible to move in any direction.
- Equivalent of the LF1 osteotomy
- vertical subsigmoidal osteotomy (VSSO)
Give 2 types of maxillary orthognathic surgery
LF 1-3
* Le Fort I osteotomy (most common)
- Cut the maxilla from the base of the skull and move it in any direction
- LF2 = maxilla and nose moved together
- LF3 = Maxilla, nose and cheek bone moved together
Anterior maxillary osteotomy
- Can’t move the whole maxilla back because of the pterygoid plates, only the anterior part is moved back
What might patient complain of it they have a sialolith? (5)
pain/pressure before mealtime
thick viscous saliva
salty saliva
dry mouth
swelling of duct which is fixed
What gland/duct is most commonly affected by sialolith and why? (3)
Submandibular most commonly than parotid due to position of gland as;
the duct has a long uphill Path of saliva secretion = flow is slow and saliva can stagnate
Saliva is thicker and more mucous like
hilum present (90 degree bend) in some cases
How do you manage siathoths
To remove the stone:
* It must be mobile
* Located
- within the lumen on the main duct distal to the posterior border of the
mylohyoid
-Distal to the hilum
-At the anterior border of the parotid gland.
If it is inflamed/ enlarged then refer patient to max fax.
What is the nerve supply for the submandibular gland?
Parasympathetic innervation from the chorda tympani branch of facial nerve which unifies with lingual branch of mandibular nerve at the submandibular ganglion.
What secretions do the submandibular gland produce?
Mixed - serous and mucous
What is the innervation of the parotid gland?
Sensory innervation – auriculotemporal nerve and greater auricular nerve
o Parasympathetic – glossopharyngeal nerve and auriculotemporal nerve
What is the nerve supply of the sublingual gland?
Parasympathetic – chorda tympani of facial nerve which unifies with lingual branch of mandibular nerve at submandibular ganglion.
What secretions do the sublingual gland produce?
predominantly mucous but some serous
What secretions does the parotid gland produce?
Serous
Patient with extra oral large swelling
What information is required when taking a history and investigating a patent with swelling before looking in the mouth? (11)
How long swelling has been present?(continued swelling after 48hrs= infection)
cause - how did it start
Pain Hx- SOCRATES
fluctuation in size
Feeling generally unwell
Problems with breathing/swallowing (straight to A&E)
Palpation (firm/mobile)
Pus
Heat
Colour.
Fever-
Any suspicion of sepsis?-urgent referral to A &E.
MH- any allergies
DH- any previous treatment that could have caused this ?
Record:
Temperature
Respiratory rate
Heart rate
pulse
O2 saturation
What things would you note about a facial swelling? (6)
size
location
Firm or soft
if mandible can be palpated
is it causing orbital swelling
encroaching on the soft tissues of the neck = airway compromised
What is the SIRS criteria?
SIRS-systemic inflammatory response syndrome
- Increased HR
pulse >90/min - Increased respiratory rate
> 20/min - temperature < 36 or >38 degrees
- WCC
< 4000 or > 12000/mm3
Px has a large extra-oral swelling - You suspect sepsis. What do you do? (2)
What is done in secondary care?(6)
- Spot and Diagnose (Take OBS e.g. O2 sat)
- Urgent call for advice/referral to Max Fax
Hospital:
- Sepsis 6
1. Give high flow oxygen
2. Take blood cultures
3. Give IV AB’s
4. Give a fluid challenge
5. Measure lactate
6. Measure urine output
What is Ludwig’s angina?
List the E/O & I/O features. (6)
Bilateral cellulitis (infection/swelling) of the sublingual and submandibular spaces (from dental infection)
- Swelling on both sides
= compromise airway
Features:
What are the extra-oral features?
- Diffuse redness
- Bilateral swelling in submandibular region
What are the intra-oral features?
- Raised tongue
- Difficulty breathing
- Difficulty swallowing
- Drooling
Name 4 maxillary and 4 mandibular spaces
Maxillary Spaces:
buccal space.
the palate
(maxillary sinus)
infraorbital space
Infratemporal region
Mandibular Spaces:
* Mental space
* Submental space
* Buccal space
* Submasseteric space
* Sublingual space
* Submandibular space
* Lateral pharyngeal space
What post op advice should be given to patients after Zygomatico-orbital fracture? (3)
Pain management, avoid nose blowing, finish course of antibiotics.
?observe for retrobulbar haemorrhage?
Where does an odontogenic keratocyst develop from?
Rests of Serres from dental lamina.
How do odontogenic keratocysts appear histologically? (4)
- Wall - Daughter/satellite cysts found within the wall
- epithelial lining: keratinised– parakeratinised
Multicentric growth – parts of epithelial lining grows faster than other sites and have finger like projections (not a nice balloon shape) - No rete pegs within the epithelium (allows the epithelium to separate from the wall)
- Palisading arrangement (basal cells at same height)
How do odontogenic keratocysts appear radiographically? (5)
- Well defined and well corticated radiolucent lesion
- A/P growth along the body, angle and ramus of the mandible
- Truly multilocular
- Can cause displacement of adjacent teeth
- Scalloped margins
**The cyst has no specific relationship to teeth **
Why are odontogenic keratocysts problematic? (3)
High risk of recurrence
Multicentric growth – parts of epithelial lining grows faster than other sites and have finger like projections
If projections left behind = reoccurrence
Daughter/satellite cysts found within the wall – if left behind they form a new keratocyst
Risk To IDN - pressure
pathological fracture of jaw
What syndrome is associated with the presence of many odontogenic keratocysts?
Basal cell naevus syndrome/Gorlin-Goltz syndrome
What does a radicular cyst develop from?
Epithelial rests of Malassez from HERS (hertwig’s epithelial root sheath)
What does a dentigerous cyst develop from?
Dental follicle at reduced enamel epithelium and crown.
How do dentigerous cysts appear histologically? (4)
- Thin non-keratinised stratified squamous epithelium
- May resemble radicular cyst if inflamed - however no inflammation usually
- Attached to the ACJ of the unerupted tooth
- flat basement membrane
- no rete pegs
How do dentigerous cysts appear radiologically? (7)
- Radiolucent with well-defined corticated margins which
- associated with cemento-enamel junction of an unerupted/impacted tooth (neck of the tooth)
- Larger cysts may begin to envelope root of tooth
- May displace the involved tooth
- Tend to be symmetrical initially - Larger cysts may begin to expand unilaterally
- Variable displacement of cortical bone (i.e. bony expansion)
- Unilocular
where are dentigerous cysts most commonly found?
Unerupted M3M and U3s.
Name 1 epithelial derived odontogenic tumour.
What is it like histologically?
Ameloblastoma
folicular ameloblastoma
- Islands present within a fibrous tissue background
- Islands Bordered by cells that resemble the ameloblast e.g. columnar cells with a dark staining nucleus
- Tissues in the middle of the follicle are loose (resemble stellate reticulum of tooth germ)
- Can be cystic changes within the follicle
- Other changes within the stellate reticulum like tissue involve squamous metaplasia or cells become granular etc
- No connective tissue capsule (in any of the types) = cells can grow and infiltrate into the jaw bone = reason for high recurrence rate
plexiform ameloblastoma:
- Amelobastoma cells arranged in strands
- Between the strands there is stellate reticulum like tissue
- Some Cells can form back to back with hardly any SR like tissue between
- No connective tissue capsule (in any of the types) = cells can grow and infiltrate inot the jaw bone = reason for high recurrence rate
adenomatoid odontogenic tumour:
- Epithelial cells arrange in duct like structures, sheets or rosette appearance
- There is a degree of calcification which are reflected in the radiological appearance
- Has a well developed fibrous tissue capsule surrounding therefore removal is easier and has a lower recurrence rate
calcifying epithelial odontogenic tumour
* Loose myxoid tissue (connective tissue) with stellate cells within
* May contain islands of inactive odontogenic epithelium (vital but inactive)
* No fibrous tissue capsule locally invasive into adjacent bone and can cause problems with surgical removal and recurrence
Name a mixed epithelium tumour.
Odontoma
Name a mesenchymal tumour
odontogenic myxoma
